2016-12-09T13:25:17ZA proposal for B-physics on current latticeshttp://hdl.handle.net/2307/226
<Title>A proposal for B-physics on current lattices</Title>
<Authors>Blossier, Benoit; Dimopoulos, Petros; Frezzotti, Roberto; Herdoiza, Gregorio; Jansen, Karl; Lubicz, Vittorio; Martinelli, Guido; Michael, Chris; Rossi, Giancarlo; Shindler, Andrea; Simula, Silvano; Tarantino, Cecilia; Urbach, Carsten</Authors>
<Issue Date>2010-04-12</Issue Date>
<Is part of>JHEP</Is part of>
<Volume>2010</Volume>
<Pages>1-25</Pages>
<Abstract>A method to extract B-physics parameters (b-quark mass and fB, fBs decay
constants) from currently available lattice data is presented and tested. The approach is based on the idea of constructing appropriate ratios of heavy-light meson masses and decay
constants, respectively, possessing a precisely known static limit, and evaluating them at
various pairs of heavy quark masses around the charm. Via a smooth interpolation in
the heavy quark mass from the easily accessible charm region to the asymptotic point, B-physics
parameters are computed with a few percent (statistical + systematic) error using
recently produced Nf = 2 maximally twisted Wilson fermions data.</Abstract>2010-04-11T22:00:00ZfB and fBs with maximally twisted Wilson fermionshttp://hdl.handle.net/2307/228
<Title>fB and fBs with maximally twisted Wilson fermions</Title>
<Authors>Blossier, Benoit; Dimopoulos, Petros; Frezzotti, Roberto; Herdoiza, Gregorio; Jansen, Karl; Lubicz, Vittorio; Martinelli, Guido; Michael, Chris; Rossi, Giancarlo; Sanfilippo, Francesco; Shindler, Andrea; Simula, Silvano; Tarantino, Cecilia; Urbach, Carsten; Wagner, Marc</Authors>
<Issue Date>2010</Issue Date>
<Pages>151-158</Pages>
<Abstract>We present a lattice QCD calculation of the heavy-light decay constants fB and fBs performed
with Nf = 2 maximally twisted Wilson fermions, at four values of the lattice spacing. The decay
constants have been also computed in the static limit and the results are used to interpolate the
observables between the charmand the infinite-mass sectors, thus obtaining the value of the decay
constants at the physical b quark mass. Our preliminary results are fB = 191(14)MeV, fBs =
243(14)MeV, fBs/ fB = 1.27(5). They are in good agreement with those obtained with a novel
approach, recently proposed by our Collaboration (ETMC), based on the use of suitable ratios
having an exactly known static limit.</Abstract>2009-12-31T23:00:00ZPseudoscalar decay constants of kaon and D-mesons from Nf=2 twisted mass Lattice QCDhttp://hdl.handle.net/2307/398
<Title>Pseudoscalar decay constants of kaon and D-mesons from Nf=2 twisted mass Lattice QCD</Title>
<Authors>ETM, Collaboration; Blossier, Benoit; Dimopoulos, Petros; Frezzotti, Roberto; Haas, Benjamin; Herdoiza, Gregorio; Jansen, Karl; Lubicz, Vittorio; Mescia, Federico; Palao, David; Shindler, Andrea; Simula, Silvano; Tarantino, Cecilia; Urbach, Carsten</Authors>
<Issue Date>2009-07</Issue Date>
<Is part of>Journal of High Energy Physics</Is part of>
<Volume>07</Volume>
<Pages>043</Pages>
<Abstract>We present the results of a lattice QCD calculation of the pseudoscalar meson decay constants fπ, fK, fD and fDs, performed with Nf=2 dynamical fermions. The simulation is carried out with the tree-level improved Symanzik gauge action and with the twisted mass fermionic action at maximal twist. We have considered for the final analysis three values of the lattice spacing, a = 0.10 fm, 0.09 fm and 0.07 fm, with pion masses down to mπ = 270 MeV. Our results for the light meson decay constants are fK = 158.1(2.4) MeV and fK/fπ = 1.210(18). From the latter ratio, by using the experimental determination of Γ(K → μbar nuμ(γ))/Γ(π → μbar nuμ(γ)) and the average value of |Vud| from nuclear beta decays, we obtain |Vus| = 0.2222(34), in good agreement with the determination from semileptonic Kl3 decays and the unitarity constraint. For the D and Ds meson decay constants we obtain fD = 197(9) MeV, fDs = 244(8) MeV and fDs/fD = 1.24(3). Our result for fD is in good agreement with the CLEO experimental measurement. For fDs our determination is smaller than the PDG 2008 experimental average but in agreement with a recent improved measurement by CLEO at the 1.4 σ level.</Abstract>2009-06-30T22:00:00Zf_B and f_Bs with maximally twisted Wilson fermionshttp://hdl.handle.net/2307/403
<Title>f_B and f_Bs with maximally twisted Wilson fermions</Title>
<Authors>ETM Collaboration; Blossier, Benoit; Dimopoulos, Petros; Frezzotti, Roberto; Herdoiza, Gregorio; Jansen, Karl; Lubicz, Vittorio; Martinelli, Guido; Michael, Chris; Rossi, Giancarlo; Sanfilippo, Francesco; Shindler, Andrea; Simula, Silvano; Tarantino, Cecilia; Urbach, Carsten; Wagner, Marc</Authors>
<Issue Date>2009</Issue Date>
<Pages>151</Pages>
<Abstract>We present a lattice QCD calculation of the heavy-light decay constants f_B and f_Bs performed with Nf=2 maximally twisted Wilson fermions, at four values of the lattice spacing. The decay constants have been also computed in the static limit and the results are used to interpolate the observables between the charm and the infinite-mass sectors, thus obtaining the value of the decay constants at the physical b quark mass. Our preliminary results are f_B=191(14) MeV, f_Bs=243(14) MeV, f_Bs/f_B=1.27(5). They are in good agreement with those obtained with a novel approach, recently proposed by our Collaboration (ETMC), based on the use of suitable ratios having an exactly known static limit.</Abstract>2008-12-31T23:00:00ZPseudoscalar decay constants of kaon and D-mesons from N-f=2 twisted mass Lattice QCDhttp://hdl.handle.net/2307/526
<Title>Pseudoscalar decay constants of kaon and D-mesons from N-f=2 twisted mass Lattice QCD</Title>
<Authors>Blossier, Benoît; Dimopoulos, Pedro; Frezzotti, Roberto; Haas, Benjamin; Herdoiza, Gregorio; Jansen, Karl; Lubicz, Vittorio; Mescia, Federico; Palao, David; Shindler, Andrea; Simula, Silvano; Tarantino, Cecilia; Urbach, Carsten; Wenger, Urs</Authors>
<Issue Date>2009-07</Issue Date>
<Is part of>Journal of high energy physics</Is part of>
<Volume>2009</Volume>
<Pages>043</Pages>
<Abstract>We present the results of a lattice QCD calculation of the pseudoscalar meson decay constants f(pi), f(K), f(D) and f(Ds), performed with N-f =2 dynamical fermions. The simulation is carried out with the tree-level improved Symanzik gauge action and with the twisted mass fermionic action at maximal twist. We have considered for the final analysis three values of the lattice spacing, a similar or equal to 0.10 fm, 0.09 fm and 0.07 fm, with pion masses down to m(pi) similar or equal to 270 MeV. Our results for the light meson decay constants are f(K) =158.1(2.4) MeV and f(K)/f(pi) = 1.210(18). From the latter ratio, by using the experimental determination of Gamma(K -> munu(mu)(gamma))/Gamma(pi -> mu nu(mu)(gamma)) and the average value of vertical bar V-ud vertical bar from nuclear beta decays, we obtain vertical bar V-us vertical bar = 0.2222(34), in good agreement with the determination from semileptonic K-13 decays and the unitarity constraint. For the D and D-s meson decay constants we obtain f(D) =197(9) MeV, f(Ds) = 244(8) MeV and f(Ds)/f(D) = 1.24(3). Our result for f(D) is in good agreement with the CLEO experimental measurement. For f(Ds) our determination is smaller than the PDG 2008 experimental average but in agreement with a recent improved measurement by CLEO at the 1.4 sigma level.</Abstract>2009-06-30T22:00:00Z